This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. In many eukaryotes, sphingolipids (SLs) are essential membrane components and play important roles in signal transduction and cell recognition. Unlike mammalian cells, which synthesize sphingomyelin and glycosylsphingolipids, the majority of SLs in Leishmania belongs to are inositol phoshorylceramide (IPC), which is are common in fungi and Trypanosomatid pathogens. Previous study studies showed that Leishmania promastigotes use SL metabolism as a major pathway to produce ethanolamine (EtN), a metabolite essential for their survival and differentiation from non-virulent procyclics to highly virulent metacyclics.